Sliding hitch assembly capture plate

ABSTRACT

The present invention provides a capture plate for preventing rotation between a trailer and a hitch assembly. The hitch assembly mounts on a vehicle, and is preferably a sliding hitch assembly. The capture plate has a lip which mates with the pin box of a fifth wheel trailer, the lip prevents rotation between the trailer and the capture plate. The capture plate has a restriction part which mates with the pin slot on the hitch assembly, the restriction part restricts rotation between the capture plate and the hitch. The capture plate has a fastener which removably secures the capture plate to the pin box.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of and claims the benefit of priorityfrom the prior U.S. patent application Ser. No. 13/037,003, filed onFeb. 28, 2011, now U.S. Pat. No. 8,672,340, the entire contents of whichare incorporated herein by reference.

BACKGROUND OF THE INVENTION

Fifth wheel trailers and tow vehicles for fifth wheel trailers aregenerally well known in the art. Fifth wheel trailers are much longer,roomier, and heavier than typical tent campers and travel trailers, andthus a fifth wheel trailer typically requires a specially modified,relatively heavy tow vehicle such as a heavy duty pickup truck. Thefront portion of a fifth wheel trailer extends over the rear portion ofthe tow vehicle so that a portion of the trailer's weight can be carriedover the rear axle of the tow vehicle. In order to accommodate theweight of the trailer a special hitch assembly is generally required.

One apparatus for allowing a pickup truck, even a short bed truck, topull a fifth wheel trailer is to use a sliding hitch assembly asdescribed in U.S. Pat. No. 6,308,977 ('977 patent). The '977 patentdescribes a sliding hitch assembly with two main parts, a base assemblyand a hitch assembly. The hitch assembly attaches to the hitch pin of atrailer; the base assembly is mounted in the bed of a vehicle. The hitchassembly is slidably mounted on the base assembly and operates bymechanically sliding the hitch pin rearward from the cab as the trailerpivots relative to the vehicle. By sliding the hitch rearward, thedistance between the hitch pin and the cab increases during turns,thereby allowing turns up to 90 degrees without the trailer contactingthe cab. To allow rotation to occur between the hitch assembly and baseassembly a capture plate is used to hold the hitch assembly in fixedrotational alignment with the trailer.

In the '977 patent, the sliding hitch assembly includes a capture platewhich is fastened to the underside of the pin box and which mates with acutout in the hitch pin slot of the hitch assembly, thereby restrictingrotation between the hitch assembly and the pin box. The capture plateof the '977 patent is a flat piece of metal which is sized to mate withthe cutout of the hitch pin slot of the sliding hitch assembly.Traditionally, the plate is either fastened directly to the pin box—suchas with bolts or screws drilled into the pin box—or by welding orotherwise mounting brackets to the pin box, with the capture plate thenmounted to those brackets.

Other prior art capture plates are constructed from a flat plate with awedge extending from the bottom side. The wedge is shaped in a Y-shapeand is sized to fill the pin slot on the hitch assembly, therebypreventing rotation between the capture plate and the hitch assembly.The top side of the capture plate has a lip which extends around theentire perimeter of the plate, with screws which mount through the lipand into or against the pin box, thereby preventing rotation between thecapture plate and the pin box.

The previous approaches to capture plate design have some drawbacks.First, each requires modification to the pin box. Second, thetraditional method of restricting rotation between the capture plate andthe hitch assembly may form too strong of a connection between thetrailer and the hitch assembly such that when rotational forces betweenthe trailer and truck become excessive, costly failure can occur in thetrailer, the vehicle, or the hitch. Third, pin box size can vary fromtrailer to trailer and thus the previous capture plate designs requirecustomized mounting hardware for pin boxes of different dimensions.

Accordingly, there exists a need for a capture plate which can beremovably mounted to a fifth wheel trailer's pin box without modifyingthe pin box. There also exists a need to design a capture plate whichwill preferentially fail so that the trailer, vehicle and hitch assemblyare protected from damage when subjected to excessive stress. Therefurther exists a need to design a capture plate which is readily andinexpensively adjustable to accommodate variously sized pin boxes.

SUMMARY OF THE INVENTION

The capture plate according to the present invention allows a fifthwheel trailer to be mounted to a sliding hitch assembly and preventsrotation therebetween. The capture plate is removably mounted on the pinbox of a fifth wheel trailer and has a lip around the top edge whichprevents rotation between the pin box and the capture plate. The captureplate has a protrusion feature, or wedge, affixed to the bottom side,which mates with the pin slot on a hitch assembly and serves to preventrotation between the capture plate and the hitch assembly. Thereby, thecapture plate prevents rotation between the trailer and the hitchassembly.

Accordingly, it is an object of the present invention to provide animproved capture plate which restricts rotation between a fifth wheeltrailer and a sliding hitch assembly.

It is an object of the present invention to provide an improved captureplate which may be mounted to a pin box without modification to the pinbox.

It is an object of the present invention to provide an improved captureplate which can be adjusted to attach to various sizes of pin boxes.

It is an object of the present invention to provide an improved captureplate which has a quick-connect fastener which anchors the capture plateto the trailer pin box.

It is another object of the present invention to provide an improvedcapture plate which has a lip that will preferentially fail in excessivestress situations in order to prevent damage to either the hitchassembly or the trailer.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred embodiment of this invention has been chosen wherein:

FIG. 1 is a fragmentary view of the trailer, truck and sliding hitchassembly.

FIG. 2 is a perspective view of the sliding hitch assembly, with thecapture plate and pin box mounted on top.

FIG. 3 is an exploded view of the pin box, capture plate and slidinghitch assembly.

FIG. 4 is an exploded view as seen from below of the pin box, captureplate and sliding hitch assembly.

FIG. 5 is an exploded view of the capture and hitch plates.

FIG. 6 is a perspective view of the capture plate mated to the hitchplate.

FIG. 7 is a perspective view of the capture plate mounted on the slidinghitch assembly.

FIG. 8 is a perspective view of the top side of the capture plate.

FIG. 9 is a perspective view of the bottom side of the capture plate.

FIG. 10 is a fragmentary view of the pin box engaged with the captureplate shown secured to the king pin by a fastener.

FIG. 11 is a top side perspective view of the capture plate with itsspacing shims in exploded form.

FIG. 12 is an alternative embodiment of the capture plate.

FIG. 13 is an alternative embodiment of the capture plate.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The embodiment herein described does not intend to be exhaustive or tolimit the invention to the precise form disclosed. It has been chosenand described to explain the principles of the invention and itsapplication and practical use to best enable others skilled in the artto follow its teachings.

FIG. 1 shows a trailer 10 connected to a sliding hitch assembly 18,which in turn is mounted to a vehicle 20. Trailer 10 includes a pin box12 with a king pin 14 downwardly extending therefrom. King pin 14engages a locking jaw 16 on sliding hitch assembly 18, thereby securingthe trailer to the hitch assembly. Sliding hitch assembly 18 is mountedin the bed of a vehicle 20 to enable the vehicle to tow trailer 10.Vehicle 20 may be a short-bed pickup truck. The sliding hitch assembly18 moves king pin 14 away from the cab of vehicle 20 when turning toprevent trailer 10 from contacting vehicle 20, such as shown in U.S.Pat. No. 6,308,977, incorporated herein by reference.

The pin box 12 is mounted on sliding hitch assembly 18 with a captureplate 22 sandwiched therebetween, as shown in FIG. 2. FIG. 3 shows anexploded view of pin box 12, capture plate 22 and sliding hitch assembly18. With capture plate 22 anchored to pin box 12, king pin 14 passesthrough a pin hole 24 in capture plate 22 and is secured in locking jaw16 on sliding hitch assembly 18, thereby connecting trailer 10 tosliding hitch assembly 18. A lip 26 restricts rotation between pin box12 and capture plate 22, and a wedge 28 restricts rotation between thecapture plate and hitch assembly 18, as discussed in more detail below.

A hitch plate 32 forms the top of sliding hitch assembly 18 and has apin slot 30. Pin slot 30 is defined as an open channel which acceptsking pin 14 and houses a locking jaw 16 which locks king pin 14 in placewhen the trailer is docked on the sliding hitch assembly. Wedge 28 isfixed to the bottom of capture plate 22 and is sized to mate with pinslot 30. Wedge 28 fits restrictively into pin slot 30 near locking jaw16 on sliding hitch assembly 18, whereby rotation is prevented betweencapture plate 22 and sliding hitch assembly 18 as shown in FIGS. 5, 6and 7. Wedge 28 may have a tapered leading edge 29, as shown in FIG. 9,such that the tapered edge serves to guide the wedge into pin slot 30 ascapture plate 22 is docked on sliding hitch assembly 18.

Capture plate 22 is formed from a generally flat plate with pin hole 24forming an aperture through the plate which accepts king pin 14 as shownin FIGS. 8-11. Capture plate 22 has a front edge 34, a back edge 36, atop side 38 and a bottom side 40. Wedge 28 extends from bottom side 40,preferably positioned between back edge 36 and pin hole 24. Lip 26extends from top side 38 and is located around a portion of theperimeter of capture plate 22, preferably around front edge 34. FIG. 8shows lip 26 traveling around nearly the front half of capture plate 22.Other embodiments envision various lip configurations such as lip 26terminating near back edge back edge 36, or extending only far enough toaccommodate shims 42, as shown in FIG. 12 and FIG. 13 respectively.Other embodiments envision lip configurations which restrict rotationbetween the pin box and the capture plate such as the use of multiplelips, or a lip contacting the back portion of the pin box or othersimilar configurations.

In one embodiment, lip 26 runs generally parallel to the outer edges ofthe top side 38 of capture plate 22. Lip 26 circumscribes a sufficientpart of pin box 12 so that rotation is prevented between pin box 12 andcapture plate 22 as shown in FIG. 13. The outer dimensions of pin box 12may vary among trailer manufacturers and therefore one or more shims 42may be secured to lip 26 to accommodate different pin boxes, therebyallowing a restricted fit between capture plate 22 and pin box 12 suchthat rotation is prevented therebetween as discussed in more detailbelow. With capture plate 22 mounted on pin box 12, top side 38, lip 26and any shims 42 contact pin box 12. Lip 26 may terminate in a flaredend 44, as shown in FIG. 8.

Shims 42 are defined as one or more spacers which may be mounted to lip26 in order to custom fit capture plate 22 to pin box 12. Shims 42 canbe secured to lip 26 by a fastening means known in the art. Here, a bolt50 passes through a hole in each shim 42 and through a correspondinghole in lip 26 and then secures into a nut 51. The number of shims 42shown in FIG. 11 is merely illustrative; the number of shims used inpractice will depend on the dimensions of the pin box to which thecapture plate is attached to allow for connection between the pin boxand the capture plate.

Lip 26 is attached to capture plate 22 with a fail-safe bond such thatthe lip may preferentially fail before the rotational force betweentrailer 10 and vehicle 20 becomes great enough to damage any of theattached components such as pin box 12, trailer 10, sliding hitchassembly 18 or vehicle 20. Lip 26 is designed to fail by bendingoutwardly or separating from capture plate 22 when subjected to asufficient rotational force, thus allowing pin box 12 to rotate relativeto capture plate 22.

Wedge 28 is an extension of capture plate 22 adapted for mating with pinslot 30. As discussed above, wedge 28 mates with pin slot 30 of hitchassembly 18 to prevent rotation between capture plate 22 and the hitchassembly. Wedge 28 may be fixed to capture plate 22 by any method knownin the art, including, but not limited to, welding, riveting, bolting,or any other fastener as is known in the art. Alternatively, wedge 28and capture plate 22 may be formed as a single piece. Wedge 28 is shapedto contact pin slot 30 to prevent rotation of the capture plate relativeto the hitch assembly. A fastener, such as a set screw 46, is carried onthe underside of capture plate 22, and serves to anchor capture plate 22to pin box 12, preferably to king pin 14. With set screw 46 tightenedagainst king pin 14, capture plate 22 is held in anchored contact withpin box 12. Fastener 46 is designed as a quick-release fastener forreadily attaching and detaching capture plate 22 to pin box 12 withoutdamaging or modifying the pin box. Fastener 46 is an improvement overthe prior art as it allows attachment of a capture plate to a pin boxwithout modifying the pin box, and does so with a single quick-releasefastener. In the preferred embodiment, fastener 46 is carried by wedge28. In the preferred embodiment, wedge 28 is fixed to the bottom side 40of capture plate 22 between pin hole 24 and back edge 36 as shown inFIG. 9. Wedge 28 may take many shapes; in one embodiment wedge 28 is ahollow D-shaped extension of capture plate 22, with a tapered leadingedge 29 to allow for smooth mating with pin slot 30. In a furtherembodiment, wedge 28 is a solid polygonal extension of capture plate 22.The description herein contemplates other embodiments of wedge 28 whichmate with a pin slot to prevent rotation between a capture plate and ahitch assembly, and which carry a quick-release fastener for readilyattaching and detaching the capture plate to the pin box withoutmodifying the pin box.

In one embodiment, the front edge 34 of capture plate 22 terminates inan angled portion 48. With capture plate 22 mounted on pin box 12,angled portion 48 serves as a ramped leading edge for engagement withpin slot 30. In an alternative embodiment, lip 50 extends the length ofthe front edge of the capture plate with arms 52 and 54 extendingperpendicular therefrom, as shown in FIG. 12. One or more shims 56 maybe secured to arms 52 and 54. In this embodiment, arms 52 and 54 areshorter in length than the embodiment shown in FIG. 8, being just longenough to accommodate shims 56. Another embodiment of the invention hasarms 58 and 60 extending from near the front edge to near the back edgeof the capture plate with shims 62 sized to fit the length of arms 58and 60, as shown in FIG. 13.

What is claimed is:
 1. A capture plate for use in combination with a pinbox and a fifth-wheel trailer hitch, said pin box is joined to a trailerand includes a king pin downwardly extending therefrom, said fifth-wheeltrailer hitch including a pin slot which is defined as a channel whichprovides access to a locking jaw, said locking jaw is adapted toreleaseably engage said king pin, said capture plate comprising: a platedefining an opening for accepting said king pin; a wedge extends fromsaid plate, said wedge is sized to mate within said pin slot; and asingle fastener removably secures said capture plate to said pin box,said single fastener is carried by said wedge and is secured againstsaid king pin.
 2. The capture plate as claimed in claim 1, wherein saidwedge includes a tapered leading edge to facilitate seating of saidwedge within said pin slot.
 3. The capture plate as claimed in claim 2,wherein said wedge is D-shaped.
 4. The capture plate as claimed in claim3, wherein said wedge is spaced rearwardly of said opening.
 5. Thecapture plate as claimed in claim 1, and a lip extending from saidplate, said lip partially circumscribing said pin box and restrictingrotation between said capture plate and said pin box, and said pin boxis not rotatable relative said trailer.
 6. The capture plate as claimedin claim 5, and a shim is joined to said lip to custom fit said lip tosaid pin box.
 7. The capture plate as claimed in claim 6, and said liphaving a flared end.
 8. The capture plate of claim 1, said plate havinga ramped leading edge.
 9. A capture plate for use in combination with apin box and a fifth-wheel trailer hitch, said pin box is joined to atrailer and includes a king pin downwardly extending from the pin box,said fifth-wheel trailer hitch including a pin slot which is defined asa channel which provides access to a locking jaw, said locking jaw isadapted to releaseably engage said king pin, said capture platecomprising: a plate defining an opening for accepting said king pin; awedge extends from said plate, said wedge is sized to mate within saidpin slot, said wedge restricts rotation between said capture plate andsaid fifth-wheel trailer hitch whereby said trailer and said fifth-wheeltrailer hitch are held in rotational alignment by said capture plate; afastener removably secures said capture plate to said pin box, saidfastener is carried by said wedge and is secured against said king pin.10. The capture plate of claim 9, wherein said capture plate is securedto said pin box only by said fastener.
 11. The capture plate as claimedin claim 9, wherein said wedge includes a tapered leading edge tofacilitate seating of said wedge within said pin slot.
 12. The captureplate as claimed in claim 11, wherein said wedge is D-shaped.
 13. Thecapture plate as claimed in claim 12, wherein said wedge is spacedrearwardly of said opening on said capture plate.
 14. The capture plateas claimed in claim 9, and a lip extending from said plate, said lippartially circumscribing said pin box and restricting rotation betweensaid capture plate and said pin box.
 15. The capture plate as claimed inclaim 14, and a shim is joined to said lip to custom fit said lip tosaid pin box.
 16. The capture plate as claimed in claim 15, sand saidlip having a flared end.
 17. The capture plate of claim 9, said platehaving a ramped leading edge.